'Normal' (or primary) snoring, not associated with episodes of apnoea or hypoventilation, is a respiratory sound generated in the upper airway during sleep, particularly deep (slow-wave) sleep and REM sleep. Nearly everyone will snore at some point in their life, and habitual snoring is also very common, affecting up to 40% of adult men and 25% of women. It is linked to obesity as well as nasal obstruction. Decreased muscle tone during sleep can result in constriction and vibration of tissues in the upper-airway, particularly those of the uvula and soft palate.
On its own, snoring typically does not cause excessive daytime sleepiness or insomnia, but it may affect one's bed partner, and therefore can often require medical treatment. Available interventions include nasal air strips (to keep the nostrils open during sleep), dental splints (to move the jaw and tongue forward), and in extreme cases palatal surgery (e.g. reducing the amount of soft palate and/or removing the tonsils to help minimize collapsibility of the oropharyngeal segment).